Okay, so I finally got this in the right forum.
A bit of background information. In my draft, a Site-wide containment breach occured. This leads to my SCP breaching containment of course. My SCP eventually encounters SCP-2315 and answers SCP-2315-1's call.

Question: Could the phone call later (about a day later) be traced to know where 2315-1's location was at the time of my SCP responding to its call?

It's not crucial to my SCP article that the call has to be traced later on, but it would make a really good addendum later on. Thank you in advance.

This page discusses how police trace phone calls. It generally involves acquiring records from a phone provider using a warrant. For mobile phones, after the call, they could retrieve cell tower location data, or which tower the call went through.

According to this article, however, that location data isn't very precise. Maybe talking about whole cities.

Both that article and SCP-2315 mention triangulation (more here), which requires measuring the strength of a persistent "roaming" signal from the cellphone from multiple towers to figure out a specific location. That can only be done during the call.